When buying an electric heater, prioritize sizing (watts per square foot), safety features (tip-over and overheat protection), and the heating technology. Choose between fast-heating fan models for localized spots, silent oil-filled radiators for steady warmth, or infrared panels for direct heating.
Most indoor heaters tend to dry out the air, lowering indoor humidity levels. Dry air can cause irritation to the respiratory tract, leading to symptoms like dry throat, cough, and nasal congestion. For individuals with chronic respiratory diseases like asthma or COPD, low humidity can exacerbate symptoms.
Ceramic heaters are great for heating up large spaces since they typically have a fan to push the heat around. Infrared heaters heat up objects, or people, instead of heating the air which makes them great for small spaces. They also produce a more comfortable heat source since it doesn't produce hot air.
Generally, a 1500-watt heater can effectively heat a well-insulated room of about 150 square feet (approximately 14 square meters) in moderate climates. For larger spaces or colder climates, additional heating sources or a higher wattage heater may be necessary.
Room Size and Heater Wattage
As a rule of thumb, a well-insulated room requires around 100 watts per square metre for adequate heating. So, for a small room of 10m², a 1000W heater would do the job nicely. For a larger room of 20m², you'd need a 2000W heater to achieve the same level of warmth.
Space heaters generally use between 750 to 1500 watts, depending on their size and type. A 1500-watt heater is the most common type for home use. Running a 1500-watt heater for one hour consumes 1.5 kilowatt-hours (kWh) of electricity.
They key is to get the right size. If the power rating or wattage of the electric heater is too small your heater will struggle, if it's too big, you'll pay more. Go for one with a higher wattage and a thermostat. The thermostat will regulate the temperature in the room by controlling the power supplied to the heater.
To calculate the cost of running a 1500-watt heater for 24 hours in the US, you need to know the electricity cost per kilowatt-hour (kWh). If the average cost is about 16 cents per kWh (as of early 2023), the heater uses 1.5 kW x 24 hours = 36 kWh. Therefore, the cost would be 36 kWh x 16 cents = 5,76.
Best for small rooms → Fan heaters are a handy choice when you want quick warmth in spaces like bedrooms, studies or bathrooms. Best for larger rooms → Panel heaters and oil column heaters are better suited to bigger living spaces where you want steady, comfortable warmth.
Even those open to alternatives may hesitate because infrared doesn't work like conventional systems. Infrared heat is quieter, cleaner, and often invisible. But because it doesn't “blow warm air” or make radiator noises, some people assume it's not working. There's also the issue of cost comparisons.
What is the safest heater to leave on overnight? It's not recommended to leave any space heater on if you're not monitoring it. But if you must, oil-filled, radiant space heaters are considered safer than ceramic convection (hot air) types, according to Roberson. Both of these options are safer than open-coil heaters.
Heaters with oscillating fans tend to be noisiest, but they're still relatively quiet and deliver heat more evenly than heaters without fans.
Studies show that temperatures that fall below freezing (32 degrees F) trigger COPD flare-ups. If it is too cold, stay indoors until it warms up.
It takes time for your home to warm up and cool down. If you're not sure how long it takes, try turning the heating on about 30 minutes before you need it. You should turn it off 30 minutes before you'll stop needing it.
The most significant downfall of indoor heating is that it causes the air to dry out. Our lungs have to stay moist in order to function properly. Exposure to dry air for a prolonged period of time can cause wheezing, shortness of breath, and other respiratory problems.
The heaters tiles radiate 30,000 BTU of warmth to provide direct comfort to you and everything around you. The heat is direct and efficient to cut through the cold, and can warm an area up to 1,000 square feet.
40,000 BTUs is a good average output table that will offer very good heating for indoor or outdoor applications. Even though a 40,000 BTU gas fire pit has only 10,000 BTU more than a 30,000 BTU table, it has almost one and a half times the heating capacity the latter.
For 700–900 sq ft, an 18,000 BTU unit is typically correct. And for a full 1,000 sq ft home - or a dedicated ductless air conditioning system for a 1,000 sq ft home - a 24,000 BTU (2-ton) unit or a multi-zone system is the appropriate solution.
The most efficient electric heater depends on how and where you use it. Oil-filled radiators are great for maintaining steady warmth and retaining heat, making them ideal for general spaces. Ceramic and convector heaters warm medium spaces quickly and evenly, while fan heaters deliver instant heat in small rooms.
Here are some features to consider:
Common problems: gas leaks, pilot light failures, and clogged burners. Electric furnaces heat homes using electricity instead of gas or oil, making them cleaner, safer, and low maintenance.
Here are the most significant home electricity users:
👉 For a 24x24 ft (576 sq. ft.) garage, that's anywhere from 17,000 to 40,000 BTUs needed—before adjusting for climate, ceiling height, and other factors.
If your home uses electricity for central heating, the cost is likely still cheaper than running space heaters. According to Scerbo, “Buying a space heater for every room would increase the electricity bill more than if you had just bumped up the thermostat.”